Description of problem:

Capsule Upgrade Playbook details missing in Release Notes of Satellite 6.18

Steps to Reproduce:

1. Refer Release Notes in below link

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https://content-preview.docs.redhat.com/en/documentation/red_hat_satellite/6.18/html-single/release_notes/index

~~~

2. Upgrade Capusle Playbook details is missing from Release notes of 6.18

3. Go to Infrastructure > Capsule > Content > Upgrade Capsule Playbook

Actual behavior:
 Details is missing for this feature in New Release sections.

Expected behavior:
 It should show details of the Upgrade Capsule playbook in New Release Sections.